The present invention relates to a method of processing silver halide color photographic light-sensitive materials. More particularly, the present invention relates to a processing method which is capable of rapid-processing, low in replenishing volume, improved in desilverizing capability, and excellent in processing stability.
In forming color images by photographic processing of an imagewise-exposed light-sensitive material, a desilvering process followed by a washing process or stabilizing process is generally provided after a color developing process. In recent years, light-sensitive materials have come to be processed in automatic provessing machines installed in processing laboratories. In such processing laboratories, there is demanded prompt service to finish processing of light-sensitive materials and return them to customers on the same day they are brought in for processing; recently, even returning within hours after bringing in has come to be requested. Accordingly, a technological development in rapid processing is ardently desired.
Under the circumstances, Eastman Kodak Company proposes a rapid processing for color paper called Process RA-4, which performs processing in 3 minutes at 35.degree. C. by three steps comprising color developing of 45 seconds, bleach-fixing of 45 seconds and stabilizing of 90 seconds.
The prior art aimed at a rapid processing of light-sensitive materials can be roughly classified into three types, namely
(1) techniques to improve light-sensitive materials, PA1 (2) techniques relating to mechanical means in processing, and PA1 (3) techniques to improve the composition of a processing. solution used in processing.
The above (1) includes [1] improvement in silver halide composition (for example, a technique to minimize the size of silver halide grains as described in Japanese Pat. O.P.I. Pub. No. 77223/1976 and a technique concerning silver halide having a low bromide content described in Japanese Pat. O.P.I. Pub. No. 18142/1983 and Japanese Pat. Examined Pub.No. 18939/1981), [2] use of additives (for example, a technique to add 1-aryl-3-pyrazolidone having a specific structure to a light-sensitive material as described in Japanese Pat. O.P.I. Pub. No. 64339/1981 and a technique to add 1-arylpyrazolidones to a light-sensitive material as described in Japanese Pat. O.P.I. Pub. Nos. 144547/1982, 50534/1983, 50535/1983 and 50536/1983), [3] techniques based on rapid reactive couplers (for example, couplers as described in Japanese Pat. Examined Pub. No. 10783/1976 and Japanese Pat. O.P.I. Pub. Nos. 123342/1975, 102636/1976), and [4] techniques relating to a photographic thin-layered structure (for example, a technique to thinned photographic component layers described in Japanese Pat. Application No. 204992/1085).
The above (2) includes techniques for stirring a processing solution (for example, a stirring technique described in Japanese Pat. Application No. 23334/1986).
The above (3) includes [1] techniques to use developing accelerators, [2] techniques to use high-concentration color developing agents and [3] techniques to reduce the concentration of halide ions, especially bromide ions.
In these rapid processing techniques, use of light-sensitive material containing a silver halide having a high silver chrolide content (a technique described, for example, in Japanese Pat. O.P.I. Pub. Nos.95345/1983, 19140/1985 and 95736/1983), which falls into (1) of the above category, can provide a particularly high rapid processability.
On the other hand, approach to rapid processing by raising desilverizing speed in desilvering process is also known. As bleaching agents used in desilverization, there have been used oxidizing agents such as ferricyanates, bichromates, persulfates and ferric chloride. However, these oxidizing agents are pollutive to environment; moreover, these are difficult to be reused by recovery, and thereby solutions after processing are compelled to be disposed of as waste.
To solve such a pollution problem as well as to meet the requirements for rapid and easy processing and for capability of recycling waste solutions, there has come to be widely used a processing solution containing a (ethylenediaminetetracetato) ferric complex salt as an oxidizing agent. But the processing solution using a (ethylenediamine-tetracetato) ferric complex salt has a disadvantage that the bleaching speed is low owing to the complex salt's slow oxidizing capability.
Though a longer processing time can prevent a poor desilverization, this is contradictory to the requirement for rapid processing.
As another method of rapid processing, the so-called bleach-fixing monobath in which a bleacher solution and fixer solution are mixed in one solution is practiced. And as a mean to accelelate the desilverization, a method of using a (diethylenetriaminepentacetato) ferric complex salt is disclosed in Japanese Pat. O.P.I. Pub. No. 149358/1984.
Further, Japanese Pat. O.P.I. Pub. No. 222252/1986 discloses a method to use ferric complex salts of diethylenetriamine pentacetic acid, cyclohexanediaminetetracetic acid and 1,3-diaminopropane tetracetic acid in combination therewith.
When a ferric diethylenetriamine pentacetate complex salt is used in a one-bath bleach-fixer solution, the desilverization speed is increased as compared with the case using a ferric diethylenetriamine tetracetate complex salt; but, it is still insufficient.
Further, when ferric complex salts of diethylenetriaminepentacetic acid, cyclohexanediamine tetracetic acid and 1,3-diaminopropane tetracetic acid are jointly used in a bleach-fixing bath, precipitation of sulfides occurs because the oxidation capability of a (1,3-diaminopropanetetracetato) ferric complex salt is too strong. As a result, the fixing capability is lowered; and when the replacement by a replenishing solution is small, tar tends to be generated and yellow stain is liable to increase.